Effects of thin GaAs insertion layer on InAs∕(InGaAs)∕InP(001) quantum dots grown by metalorganic chemical vapor deposition

We studied the influence of a thin GaAs insertion layer (5–10 monolayers) on the optical properties of InAs QDs grown by metalorganic chemical vapor deposition. The insertion of a 10 monolayer (ML) thick GaAs layer on the InAs QDs led to significant photoluminescence blueshifts of 54 and 111meV when they were grown on InGaAs and InP, respectively. In addition, a narrowing of full width at half maximum was observed when the thicker GaAs insertion layers and higher overgrowth temperature for the top capping layer were used. These results can be applied for tuning the emission wavelength around 1.55μm for optical fiber communication.